Regarding content changes:
I think that epic jewels might affect the balance of the server even more. Also enchantment of arcane power will be broken too.
Regarding rates changes:
This thing about making the server x25 is something that I strongly dislike because I came here to play a low rate server and not a mid-rate one. Merging it with x5 interlude server should be ok. It will bring more people that played on low rate server so the balance should be fine. Also you will keep current low rate lovers.